Sucrose substitutes sucralose

Substituent effect, additivity of, 570 electrophilic aromatic substitution and, 560-563 summary of. 569 Substitution reaction, 138 Substrate (enzyme), 1041 Succinic acid, structure of, 753 Sucralose, structure of. 1006 sweetness of, 1005 Sucrose, molecular model of. 999 specific rotation of, 296 structure of, 999 sweetness of, 1005 Sugar, complex, 974 d, 980 L, 980... 

Sucralose (2), 4,l, 6 -trichloro-4,l, 6 -trideoxy-ga/actosucrose (TGS), is a trichloro disaccharide nonnutritive sweetener.18 This compound was discovered through a systematic study in which sucrose derivatives were prepared. It was found that substitution of certain hydroxy groups by a halogen increased the sweetness potency dramatically.19 20 Sucralose was chosen as the development candidate by Tate and Lyle.21-24... 

Selective chlorination of sucrose, by which three of sucrose s hydroxyl groups are substituted with chlorine atoms, produces sucralose (l,6-dichloro-l,6-dideoxy- S-D-fructofuranosyl-(24>l)-4-chloro-4-deoxy-a-galactopyranoside) sweetener sold as Splenda [49]. Sucralose is approximately 650 times sweeter than sucrose and can be used in baking. Its synthesis involves treatment of a partially acetylated sucrose with sulfuryl chloride the initially formed chlorosulfate esters act as leaving groups and undergo nucleophilic displacement by chlorine [20]. Sucralose was first approved for use in Canada in 1991 as of 2006, it has been approved in over 60 countries. 

Sucralose may be prepared by a variety of methods that involve the selective substitution of three sucrose hydroxyl groups by chlorine. Sucralose can also be synthesized by the reaction of sucrose (or an acetate) with thionyl chloride. 

People who want to avoid sucrose in their diet often use a sugar substitute, such as sucralose, shown in Figure 14. These substitutes have shapes similar to that of sucrose, so they can stimulate the nerve receptors in the same way that sucrose does. However, sucralose has a different chemical makeup than sucrose does and cannot be processed by the body. 

Sucralose is chemically very similar to sucrose. Both have the same three-dimensional shape. However, three Cl atoms have been substituted in sucralose, so the body cannot process it. 

Note that sucralose (marketed under the trade name Splenda) differs from sucrose in the substitution of chlorine for three hydroxyls. 

Substitution of one or more of the -OH groups of sucrose by a -Cl atom has a profound effect on its taste thus it may greatly increase the intensity of its sweetness or abolish it altogether. The most promising of these chlorinated sugars as an alternative sweetener is Sucralose which has a Cl atom substituted on carbon atoms 4,1 and 6. It is 650 times sweeter than sucrose itself, lacks the unpleasant aftertaste of saccharin and gives no evidence of any adverse effects. It will be interesting to see if it becomes a commercial success. 

There are a number of sugar substitutes, or artificial sweeteners on the market the most popular are saccharin, aspartame, sucralose, and cyclamate. Many of these were discovered by accident, when a chemist did something you re never supposed to do in a chemistry lab - lick your fingers. In the case of sodium cyclamate, the graduate student had put his cigarette on the side of the lab bench (yes, you were allowed to smoke in chemistry labs in 1937 ), and when he put it back in his mouth it tasted sweet. The advantage of these artificial sweeteners comes from the fact that they are often many times as sweet as sucrose, which means you don t need to use very much of them, and also that they are not metabolized in the same way as sugar, so you don t get fat. They also don t cause tooth decay. 

Still Other halo-substituted compounds are used as medicines and food additives. The nonnutritive sweetener sucralose, marketed as Splenda, contains four chlorine atoms, for instance. Sucralose is about 600 times as sweet as sucrose, so only 1 mg is equivalent to an entire teaspoon of table sugar. 

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